Switch mechanism



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SWITCH MECHANISM Filled March 7, 1927 ggf-m.

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itfilay it?, 1193@ ERNEST .91. BHLMAN, OF CHGLF, LLN-SIS, ASSIGNOR TOKELLOGG SWITCHBGABD AND SUPPLY COMPANY, @F CHAG, ELLINOIS, A.CORPORATION F ILLINOIS starren mechanism- Appieation nie@ farch Fi,

My invention relates td tuning couplers vor transformers used in radioreceiving systems, and has to do more particuiariy with tuning couplersor transformers in which the inductance of one of the windings of thetransformer is varied in steps by means of a switch arrangement, and anobject of my invention resides in a novel method of construction andoperation ofthe same.

y@ A feature of my invention has to do with Athe contact structure towhich the taps from the tapped windings of the transformers are secured,and the novel means employed for securing the contacts to the supportingpanels.

Another feature of my invention has to do with the manner in which thewiper arms for varying the inductances of the windings of thetransformers by steps are associated with 2o a single controlarrangement. istill further feature of my invention is the provision ofa novel arrangement in association with the wiper arms of thetransformers to provide means for connecting the said wiper arms withthe external circuits.

The above features as Well as others not specifically pointed out willbe morel fully described and explained in the ensuing specication, andfor a more complete understand- 3o ing of my invention reference may behad to the accompanying drawing in which like reference characters inthe several views denote like parts, and in which:

Fig. 1 is a front elevation of the switching mechanism of my inventionin association with a pair oftransformers,

Fig. 2 is a plan view of Fig. 1,

- Fig. @vis a sectional view along the line p idf-3 of Fig. 1 andclearly illustrates the means which controls the wipers that-engagecontacts associated with the tapped secondaries of the transformers,

Fig. 4 is a sectionalview along the line 4-4-4 of Fig. 1, and

ing the switching mechanism of my invention Fig. 5 is a perspective viewof a contact 1827. Seriai No. 173,325?.

is associated with a pair of transformers -T and '1" comprising statortubes 2 and 3. Mounted within the stator tubes`2 and 3 are rotatablerotor tubes or elements i and 5 shown in dotted lines in Fig 1. Thestator tubes or elements 2 and 3 are mounted upon a base board 6 by Ushaped brackets 7 which are provided with diverging legs 8 and 9 whichhave tapped orifices, and screws, 10 which pass through suitableorifices in the stator tubes 2 and 3 have threaded engage,

ment with the tapped orifices in the respective legs 8 and 9 of thebrackets 7 to secure 'them to the bracket 7, the said bracket 7 being inturn secured to the base board 6 by suitable screws. The rotor tubes tand 5 are supported on a rod 11 of suitable insulating ma.- terial andmay be rotated 90 degrees or until they are at right angles to the axisof the stator tubes 2 and 3. f

The stator coils SC and SC are tapped and these taps are led to contacts12 mounted on the panels 713 and 14, and as the contacts 12 are mountedon the panels 13 and 14; in a similar manner andare of'similarconstruction and arrangement the description of one will suffice for aclear understanding of the same. The panel 13 'associated with thestator coil SC is rectangular in shape and of suitable insulatingmaterial such `as bakelite and is provided with anarcuate' shaped end15. The panel 13 is also provided with a suitable opening 16, the topedge 17 of which is arcuate and concentric withthe arcuate end 15 of thepanel 13. The arcuate end 15 of the panel 13l and concentric arcuateedge 17 of the orifice 16 in the panel 13 form an arcuate shapedbridging member 18 to which the conloo l panel 13 and arcuate edge 17 ofthe opening 16 and are of a size and depth to receive respectively theangular extended portion and integrally formed angular extending tongue21 of the contact 12 to place the body 19 of the same against the face24 of the panel 13. -The respective ends .of the portion 20 and tongue21 extend rearwardly from the rear face of the panel 13 and to securethe contact 12 in position against displacement the extending end of thetongue 21 is bent substantially parallel with the-rear face of the panel13 and an intermediate portion of the angular extension 20 is lalso bentsubstantially parallel withl the rear face of the panel 13; The end ofthe angular extension 2O is now bent at right angles to the intermediateportion which is substantially parallel with the rear face of the panel13 and extends rearwardly and serves as a terminal to which a tap orlead from the tapped stator coil SC is fastened by suitable means suchas solder. The end portion 19 of the body 19 of the contact 12 extendsbelow the arcuate edge 17 of the opening 16 in the panel 13 and 1 showseven contacts 12 secured as above`described and these end portions 19are' arranged in an arc of a circle and a double wiper arm W comprisingWipers 25 and 26 is adapted to wipe over the end portions 19 of thecontacts 12.

While 1 have illustrated but two transformers T and T provided withtapped stator coils SC and SC associated with the panels 13 and 14carrying contacts to which the taps from the respective coils are ledand in which the wipers W are multiply controlled it is to be understoodthat any number may be provided,

and the wiper arms W, associated with theA contacts 12 may be multiplycontrolled and adapted to be moved corresponding distancessimultaneously so that the inductan'ces of the transformers T and T maybe varied by placing a dierent number of turns in circuit. By using amultiple control device the same number of turns will be used oneachcoil, and thus efficient results `will be obtained.

The panel 13 associated with the transformer T is located forward of thesame and is secured to the integrally formed angular extensions 30 and31 of the U shaped bracket 7 which supports the stator tube 2, by meansof 4screws 32, which pass through orifices in the panel 13 and havethreaded engagement with tapped orifices in the extensions 30 and 31.Additional securing means for the Vpanel 13 in the form. of brackets 33are secured to the 4said panel 13 by means of rivets 34. f The brackets33 are provided with integrally fomerd pin members 35 which extendthrough orifices 36 in ythe stator tube 2 to- Irigidly secure the upperportion of the panel against movement. A bushing 37 provided Y ywith areduced portion 38 is inserted into a suit- Haasse this protrudingportion is upset or spun over shaft extends into the said orifice 47 ofbushing 45. The one end of the shaft 42 protrudes slightly into thecircular orifice 46 of the bushing 45 and this protruding end is stakedover to secure the bushing 45 to the shaft 42. A shaft 48 extendsthrough an orifice 49 in the frontpanel 50 into the orifice 46 in thebushing 45, and a set screw 51 having threaded engagement with asuitable tapped orifice in the bushing 45 engages this shaft 48 torigidly secure the same in the said bushing. The wipers 25 and 26 of thewiper arm W are provided with substantially circular portions 25 and 26which are provided with orifices 52 of a size and shape to fit over theformed end 43- of the shaft 42 and these circular portions 25 and 26 ofthe wipers 25 and 26 when positioned on the stub shaft 42 rest betweenlthe bushing 37 in the panel 13 and the face of an arm 53 secured to thebushing 45. It is readily apparent that as the shaft 48 is turnedthrough the medium of a suitable knob secured to the end protrudingthrough the panel 50, the bushing 37, and the stub shaft 42 securedthereto and the wipers 25 and 26 which are supported on the stub shaft42 are rotated as a Whole causing the free ends 252 and 262'of thewipers 25 and 26 to engage the opposite faces of successive contacts 12as it is rotated from left to right and vice versa, through the mediumof the shaft 48. The arm 53 secured to the bushing 45 is also rotatedand this movement of the arm 53 is for purposes as will presently bedescribed. A racket 60 secured to the panel 40 by screws 32 is .providedwith an upwardly extending portion provided with an vorifice 61 throughwhich the shaft 48 extends and serves as a bearing when the sameisrotated, and the bushing 37 secured to the panel 13 and through whichthe stub shaft 42 extends serves as a bearing for the shaft 42 when itis rotated through the agency of the shaft 48 as just described. Y r

To prevent any overrun of the free ends 252 and 262 ,of the wipers 25and 26 as they pass from one contact 12 to the next and also to producea snap action as the wipers 25 and 26 pass from one contact 12 to thenext, the arm panel 13. The bracket 60, secured to the panel attacca 13as already described is provided with an orifice 64 adapted to receive aball bearing 65.

A. leaf spring 66 secured at its one end to the bottom face of thebracket has its free end engaging the ball bearing which rests in theorifice 64 to maintain the same in engagement with the notches 63 in theextended portion 62 of arm 53. rIhe ball bearing 65 cooperates with thenotches 63 in the extended port-ion 62 of the arm 53 and as the shaft 48is rotated, the arm 53 is also rotated causing a tooth 68 formed by twoadjacent notches 63 to engage the ball bearing 65 and force it downagainst the normal tension of the spring 66 and as the arm 53 continuesits rotation the hall 65 passes the tooth 68 and acts upon the nextnotch 63 under the influence of the spring 66 so as to givea quick snapaction to the wipers 25 and 26 of the contact arm W as they pass fromone contact 12 to the next.

rllhe wipers 70 and 71 associated` with they wiper arm W of thetransformer T are rotatably supported in a manner similar to thatdescribed in connection with the wipers 25 and 26 and will now bedescribed. A bushing 72 is 'secured to the panel 14 by staking itsprotruding end and is provided with a central orifice which receives astub shaft 73. The stub shaft 73 is provided witha flat portion 74 andthe wipers 't0 and 71 and arm 7 5 are provided with orices shaped topermit them vbeingl slipped over the end of the stub shaft 73. The shaft7 3 protrudes slightly beyond the face of the arm 7 5 and thisprotruding end is staked to secure the (wipers 7 0 and 71 and arm 7 5 tothe stub shaft 7 3.

A link 80 provided with a bifurcated end 81 is associated with the freeends of each of the arms 53 and 75, The bifurcated ends 81 straddle thearms and are pivotally secured thereto by means of pivot pins 82. Eachlink is provided with an orifice 83 which is adapt ed to receive a rod84. Set screws 85 having threaded engagement with suitable tappedorifices in the ends of thelinks 80 engage the rod 84 to rigidly securethe rod 84 to the links 8() to connect the rod 84 with the arms 53 and 75 associated with the wiper arms W and W comprising respectively wipers25, 26 and 70, 71. lt is readily apparent that when the shaft 48 isoperated through the agency of a suitable mechanism secured thereto; the

arm 53 secured to the bushing 45 to which the shaft 48 is secured isrotated and through the agency of the links 8O which connect the arms 53and 7 5to the connecting-rod 84 the movement of the arm 53 istransmitted to the arm '7 5 to move them simultaneously.

The arms 53 and 7 5 are' provided with de' pending legs 9() which arespaced apart so as to span the wipers 25 and 26 and wipers 70 and 71 ofthe wiper arms W and W.v The arm 53 is associated with the stub shaft 42as before described and the movement of the arms 53 and 7 5 causesrotationof the l'stub shafts 42xand 'I3 and as the wiper arms W and I Ware secured thereto their free ends are rotated from one contact to thenext. A pair of stop pins 91 secured to the panel 13 are provided tolimit the movement of the wipers 25, 26 and 70, 71 of the wiper arms Wand VV, from left to right and vice versa, the stops 91 of course beingengaged by the respective edges of the depending portion 62 of the arm53.

Disks 93 having orifices of a size to fit over the reduced portion ofthe bushings 37 and 7 2 secured to the panels 13 and 14 are providedwith extended portions 94 which are secured to the panels 13 and 14 bymeans of suitable screws. IThe extended portions 94 are so formed thatwhen the disks 93 are positioned on the bushings 37 and 72 between theface of the panels 13 and 14 and the circular portions 25 and 26' and 70and 71 of the respective wiper arms W and W, the said `disks 93 areplaced under tension. The faces 95 of the disks 93 are provided with aplurality of embossed portions 96 formed by a suitable punch pressoperation and these embossed portions firmly7 engage the faces of thecircula'r portions 26 and 71 of the wipers 26 and 71 of the respectivedouble wiper arms W and W to provide rubbing contacts between the disks93 and the circular portions of the respective wipers 26 and 71.The'extended portions 94 of the disks 93 are provided with integrallyfornied terminals 98 to which external conductors are connected andthrough the agency of the extensions 94 and the disks 93 which are incontactual engagement with the circular portions 26 and 71 of the wipers26 and 71 of the respective wiper arms W and W current is thus carriedto the wipers.

While l have illustrated and described a preferred embodiment of myinvention it is to be understood that l do not wish to be limited to theexact structure as shown but aim to cover all such changes andmodifications as come withinthe spirit and. scope of the appendedclaims.

yHaving described4 my invention what I claim is new and desire to secureby United States Letters Patent is: y

1. A device of the character described including a mounting panel havingan orifice therein, contacts mounted flat against said panel having anintegrally formed portion extending into said orifice and a pair ofintegrally formed portions adapted to secure said contacts to saidpanel, and a wiper arm extending into said orifice and engaging the saidfirst extending portion of said contacts.

2. A device of the character described includingV a flat mounting panel,contacts having integrally formed members for securing said contactsflat against the said panel, and a .pair of wipers for engaging theopposite sides of said' contacts.

parallel With said arcuate end to form an` arcuate bridging member, aplurality oi flat w contacts having an integrally formed portion'extending into said orifice and arranged in an arc of a circle andsecured to said bridging member, and a Wiper arm eomprising a pair ofWipers supported on a rotatable shaft adapted to' engage respectivelythe opposite faces of the extending portion of said contacts. Y

5. A device of the character described including a mounting panelprovided with an arcuate shaped end, said panel having an orificeprovided with an arcuate edge parallel to said arcuate end to form anarculate bridging member, notches in the respective edges of saidbridging member, contacts provided With integrally formed membersresting in said notches, said members protruding beyond said panel toprovideimeans for securing said contacts to said bridging member of saidpanel. f

6. A device of the character described including a mounting panelprovided With an `arcuate shaped end, said panel having an orificethereln provided with an arcuate edge parallel with said arcuate end ofsaid panel to form an arcuate bridging member, notches in the respectiveedges of said bridging members, contacts provided with integrally formedangularlyv extending members resting in said notches, said membersprotruding beyond said panel to providel means for securing saidcontacts to said bridging member f' of said panel, and a Wiper armcomprising a pair of Wipers supported on a rotatable shaft adapted toengage respectively the opposite faces of said contacts. i

7. A device of the character described including a mounting panelprovided With an arcuate shaped end, said panel having an ori- `ticethereinA provided Wit-h an arcuatefedge parallel-With said arcuate endto form an arcuate bridging member, notches in the respective edges ofsaid bridging m'embers,

contacts each provided With a pair of' integrally formed angularlyextending members adapted to rest in said notches and projecting beyondthe face ofsaid panel, one of each ofy said pair on angularlyv extendingmembers being bent parallel to said panel, said other of said pair bfextendingrmembers having an intermediate portion bent parallel withmeeneesaid panel, said bent portions securing said contacts to saidbridging member.

8. A device of the character described including a mounting panelprovided With an arcuate shaped end, said panel having an orificetherein provided With an arcuate edge parallel With said arcuate end toform an arcuate bridging member, notches in the respective edges of saidbridging members, contacts each provided With a pair of integrallyformed angularly extending members adaptedvto rest in said notches andprojecting be yond the' rear face of said panel, one of each ofsaidpairof angularly extending members being bent parallel to said panel andsaid other of said pair of extending members having an intermediateportion bent parallel with said-panel, said bent portions securing saidcontact to said bridging member, the said end of said other of' saidextending members being angularly displaced relative to its intermediatebent portion to form a terminal for said Contact. v

9. A device of the character described including a mounting panelprovided with an arcuate shaped end, said panel having an orilicetherein provided With an arcuate edge parallel With said arcuate end toform an arcuate member, contacts each of Which is yprovided With a pairof integrally formed angularly extending members adapted to rest in saidnotches and projecting beyond the rear face of` said panel, one of eachof said pair oi' angularly` extending'memb/ers being bent parallel tosaid panel and said other of said pair of extending members having anintermediate portion bent parallel With said panel, said bent portionssecuring said contact. to said bridging member, a-nd a Wiper armcomprising a pair of Wipers supported on a rotatable shaft adapted toengage the opposite faces of said contacts.

10. A device of the character described including a mounting panelprovidedWith an arcuate shaped end, said panel-having an oritice thereinprovided Withan -arcuate edge y parallel with said arcuate end to forman arcuate bridging member, notches in the respec tive edges of saidvbridging members, contacts provided With integrally formed angularly`extending members resting in said notches,

said extending members protruding' beyond said panel to provide meansfor securing said contacts to said bridging member of said panel, aWiper arm comprising a pair of Wipers and anarm supported on a rotatableshaft, said pair of wipers being adapted to engage respectively theopposite faces of said contacts, and means integrally formed with saidarm cooperating With springpressed means for maintaining the said Wipersin en-Y gagement with the selected contact.

l1. A device of the character described illtacts having integrallyformed portions eX- tending into said orice secured against the yarcuateshaped side of said panel by means extending through said panel, and apail1 of Wipers rotatably secured on one` side of said panel forengaging the opposite sides of said l March, 1927.,

contacts.

l2. A device of they character described inf cluding a panel having anorifice with an arcuate shaped side, contacts having an integrallyformed portion, extending into said" orifice and secured Hat against theextending portion of said panel, and a pair ofwipers rotatably supportedon one side of said panel for engaging the opposite sides of saidcontacts.

13. A device of thecharacter described including a mounting panel,contacts secured.

to said panel, Wipers secured to a rotatable shaft supported by saidpanel, said Wipers adapted to engage both sides of said.contacts,

and a Wiper arm having side portions adapted to extend on each side ofsaid wipers to control the operation of said Wipers.

Signed by me at Chicago, in the county of Cook and State of Illinois,this 4thday of ERNEST A. BOHLMAN.

